JOURNAL OF ROCK MECHANICS

JOURNAL OF ROCK MECHANICS

Development of a geometric model of a 3D fractal discrete fracture network for tunnel sealing design selection

Document Type : Original Article

Authors
1 PhD graduate in Engineering Geology, Tarbiat Modares University
2 Faculty member, Department of Engineering Geology, Tarbiat Modares University
3 Faculty member, Department of Mining, Petroleum and Geotechnical Engineering, Shahrood University of Technology
4 PhD graduate in Engineering Geology, Kharazmi University
Abstract
Rock masses consist of intact rock and discontinuities such as fractures, which strongly control their mechanical and hydraulic behavior. In sensitive analyses, including tunnel stability assessment and groundwater inflow simulation, uncertainty in fracture network modeling can significantly affect the results. Accurate characterization of fracture parameters such as orientation, density, and effective length is therefore essential. Discrete Fracture Network (DFN) modeling is widely used to represent fractured rock masses. In this study, a numerical code was developed to generate three-dimensional fracture networks using both conventional statistical DFN and fractal-based DFN (FDFN) approaches. Key fracture parameters, including position, density, dip, dip direction, and length, were simulated in both frameworks. The developed methodology was applied to the Imamzadeh Hashem tunnel as a real case study. Hydraulic fracture networks were constructed, conductive flow paths were identified, and an optimal tunnel grouting pattern was designed. The results demonstrate the critical role of fracture geometry representation in hydraulic analysis and grouting optimization
Keywords
Subjects

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